1. Field of the Invention
The present invention relates to a composition for an oral cavity, which suppresses initial adhesion of intraoral bacteria to teeth and periodontal tissue. The present invention further proves a method of preventing formation of a biofilm in an oral cavity.
2. Description of the Conventional Art
A biofilm is a film covering the surface of a microbial cell in conjunction with a substance or a precipitate secreted by bacteria when microorganisms (i.e., bacteria or the like) adhere to the surface of an object or an organism tissue and proliferate. An example of a typical biofilm in an oral cavity is plaque (bacterial plaque).
The genesis of oral cavity biofilim formation of the biofilm is an organic ingredient, such as protein or the like, in saliva coming into contact with the enamel surface, followed by a part of the organic ingredient adhering to the enamel, and thereby forming a pellicle. When an intraoral bacteria (e.g., Streptococcus sanguis) in the saliva comes into proximity with a tooth and contacts the pellicle, the intraoral bacteria is adsorbed to the pellicle, and a part of the bacteria adheres on the pellicle as it is. The adhered intraoral bacteria grows to the strong biofilm adhering to other bacteria. The adhesion of the other bacteria typically results from polysaccharides having tacky adhesiveness. These polysaccharides are knows as glucan or fructan and are made by using the nutrient or the like in the saliva. Subsequently, the bacteria in the biofilm repeats the proliferation to produce acid. Thereby, dental caries, periodontal disease or the like results.
Various method shave been researched to solve these problems. For example, an antibacterial agent and its assistant agent were proposed. As the assistant agent, antibacterial and antifungal assistants were proposed as a composition for an oral cavity including a biofilm suppressing assistant such as xylitol, farnesol or the like (for example, refer to Japanese Patent Laid Open No. 2002-302404, 2002-284604). However, since these antibacterial and antifungal assistants primarily serve to remove the biofilm, use of the antibacterial agent is indispensable.
It is known that the antibacterial agent problematically generates bacterial resistance and also sterilizes indigenous bacteria existing in the oral cavity. Therefore, there are limits to the use of antibacterial agents in a composition for an oral cavity.
Additional studies have attempted to add a protease, which is an enzyme decomposing protein, to an oral composition (for example, refer to Japanese Patent Laid Open No. 06-262165). However, since a protease is an enzyme, and as such there are problems associated with the time required to produce an effective result. Further, since proteases do not generally discriminate on the basis of protein identity beneficial proteins contained in the saliva are also decomposed.
Another attempt at solving the aforementioned problems have centered on the use of monoclonal antibodies (for example, refer to Japanese Patent Laid Open No. 2002-114709). The monoclonal antibody suppresses glucosyltransferase, which is enzyme secreted by Streptococcus mutans bacteria when producing glucan. However, if the biofilm is already formed, the effect with respect to the proliferation of the intraoral bacterial is hardly obtained. Additionally, the use of monoclonal antibodies also raises safety concerns since the monoclonal antibody originating in the mouse is applied to the inside of an oral cavity of person.